Railway switch operating apparatus



April 2, 1935. R. M. GILSON 1,996,198

RAILWAY SWITCH OPERATING APPARATUS Filed Oct. 11, 1932 B 16 21 1 25, E5 B 51 Z 18, '-i 27 3 '19 I ZZ A T i j '10 I TL 17 52 g 22 10 S INVENTOR Robert M. 6128012 HIS A TTORNEY Patented Apr. 2, "1935 UNITED A E-S "RAILWAY SWITCH OPERATING 'KPPARATUS Robert i: M. "Gilson; :Pittsbur'gh, -:'Pa., i 'assignor -to The Union-Switch & signal Company, -Swissvale, Pa.,' a. corporation of Pennsylvania v Ammonia-pewter'11, 132;"*Serial No.637,243 I ia-claims; (01. 246-242) changer P is reversedj'thicircuitwillbe th -seine invention-relatesto apparatus for thefbperation of railway switches, and particularly" to apparatus of thetype involving a'n electric motor for moving the switch'to'its'normal and reverse 5 positions. One f'eatureof my invention-isthe provision of novel 'andimproved means for protecting the motor against damageiin the event that the switch becomes stalled.

I will-describe twoforms of apparatus embodying my invention, and will 'then point out the novel featuresthereof-in claims.

"The present application is a continuation in part of-my ccpe-nding application, file-d 'Oct. 9, 1929, Serial No. 398,308, for'Railway switchlopcrating apparatus, in so 'far asthe subject matter which is operated by an electric motor M', through the medium of suitable operating mechanism which is not shown in'the "drawing, but which is indicated by-thedotted line between the motor and the switch. "The motor com risesthe 'usual armature l ari'd'field Winding 2. *Th'eswitch operating mechanism includes alcoritact' 1 -8 which is closed at all times except whenithe' switch isin its reverse' 'position, and another contact 1 1-9 which is closed at all times except'whentheswitch isinits normal position. a v

T Themotor Mis controlled primarily by a polarized relay 0. Overload "pr'otectionis provided by a thermal relay Tcompri-sing a heating element lfl and a normally 'closed'contact H. Associated with the thrmal'relaydflisan overload relay -A which 'may be of the ordinary neutral type. v M f The pclarized relay C is controlled by a polechanger P which will" usuall be. 'o eratediby a manualieverm aninterlocking machine. 'Relay C is energized by current of normal" or reverse polarity according'asthe pole ch'anger P is in its normal or reverse position. As'shown in the drawing, thisrpble-changer is inits normal position, sothat relay 0 is si pplie'd with current of normal polarity by virtueof a circuit whichpasses from terminal -B of a suitable source of current,

through --the pole-changer P,-contact of relay C and contact 13 of relay- A in multiple; winding of relayq -and the pole-changer? to terminal 0 of the samesource -ofcurrent. when -the poleas before, except that current of reverse polarity will'b'e supplied to relay TC.

TRelay' A.is,provided with a'pick-s-jup" ircuit which 7 passes-from terminaF-B, through the balckpoint of contact! of mayo; Winding-0f relaynanu' contactil-l of thermal relay' T' to 'terniinalfo;

Relay A-isalso provided with a stick circuit which passes from terrninal 'B,"throuiglffront Contact I12- of relay A, "Wii'i'dii'ighf relay. Aandthernial relayrconta'ct l lito term'inalijor 'I'he i peratior'i of the apparatususTas'fmHOws; a

As shown in "thedrawingfallmarts areffiiilstheir normal conditions, that is, re1ay' A is fen'efgized by virtue of its stick circuit; relay 'C isje'nenglzed in the normal direction, 'a'ndithe circuit "for ,moftor M; is open at switch'operatedcontactj1+9.

WI wnrnowassumeithat'the 'operatorjdesiresto reverse the i's'witch S. "'ITo dohtliisghe. i'reverses pole chang'er P; thereby' supplying-current ,o'f lreverse polarity to relay C, so. that e,po1ar ;cone

tacts 5-and 6. of 'this' -relaysviing toftheiri ghtf Motor Mwill thenfbelenergized' in 'such'idirebtion motor field 'Z, heating element Ill-of rlayTT' and front "contact 4 of relay A .to terminal 0.? When the switch S reaches its Lreverse'i positiom this motor circuitwill be. opened at contactfitg" so that them'otor willlsto'p. To restore the switch to'its normal positioriithe operator will restore. pole-changer P toi'tsnormal position, "thereby supplying current of normal polarity to relayc, pe arcontactsjof this. relay will .swingto the left, The motcfM willithenib'e energizectirl such-"direction asl'to returnthe switchS to-its normal'positiom'jthe'cirr being-from teammate-through th'ffront point of contact '4fofrelay7C, polar contact 6,

'motor armature l,- polar icontactevswitch-i contact 1 -9, motor field' 2', thermal-relay relement H3, and contact M of relay Alto terminal-0'; Whe the switch reaches I its normal position,

"this circuit will be opened at contact 'l 9 and all parts of theapparatus will be reStOredFto Itheilr,

normal conditions.

I will now assume-that While the-.svvitcli isbeing moved from. its normalto its reverse. position; the

switch becomes blocked,-so that ani e$cessive1current will be-drawn by the motor M, .Thiscflrre'fit f-lowing r through the heating} element Tl II Sofiithe. thermal/relay T.willicause contact'fl'lf of lay to open, thereby opening the stick circuit for relay A, so that the latter relay will become deenergized. The motor circuit will then be opened at contact M of relay A. The operator may immediately restore the lever to its normal or its normal indication position, after which he need take no further action until the indication is reswitch S to its reverse position, and this may be repeated indefinitely if necessary. .;.The reason for closing the circuit for relay C through contact 3 of this relay is to prevent the neutral armature, of this relay from dropping when the overload relay A becomes opened due to an overload on'motor M; if, contact 3 were not providdgrelay C would become denergized as soonas' relay A'opens due to the overload, and this would allow the overload relay A to pick up assoon as contact H of thermal relay T closes,

, thus permittinglong continued successive applications of heavy current to the switch motor underblocked conditions, which continued .ap-

plications would probably result in damage to the. motor.

Referring now to Fig. 2, in which I have provided a separate thermal relay for each directionof motor rotation, the apparatus of this .figure permits the operator to restore an obstructed switch to its initial position immediately, without the necessity for waiting .until a thermal relay cools sufliciently to reclose its contact, following an overload.

' With the apparatus'in the normal condition as shown, if the operator desires to reverse the switch, he will reverse pole-changer P, reversing relay D, so that current will be supplied to motor M over a circuit starting at one terminal B, front contact l5 of relay D, wire I 6, front contact I! of relay E, wires l8 and I9, polar contact 20 of relay D, wire 2!, armature l of motor M, wire 22, polar contact 23 of relay D, wire 24, heating winding [0 of relay T wire 25, controller contact l-8, wire 26, and field winding 2 to ter- .minal 0. Motor M will now move the switch tov the reverse position.

Shouldthe operator wish to restore the switch to the normal position, he will restore. pole- .chan'ger P and therefore relay D to the condi- 'tion shown, whereupon motor M will be supplied with current of the proper polarity for restoring the switch to the position illustrated. The

motor operating circuit will be similar to that described above, but will include heating winding ID of thermal relay T instead of the corresponding windingof thermal relay T It will benoted that the holding circuit for overload relay E, which withthe'apparatus in V the condition shown, may be traced from one terminalB, front contact 21 of relay E, wire 28, polarcontact 29, wire 30, thermal contact ill-32 of relay T Wires 33, 34 and 35, and winding of relay E to terminal 0, includes either the thermal contact of relay I or T according to the positionQof polar contact 29 of relay D. That is, simultaneously with the'transfer of the motor circuit to one or the other thermal relay by a reversal of relay D, the holding circuit for relay E will be automatically transferred to the thermal relay then effective. Overload relay E will be maintained energized during a reversal of relay D, because, since back contact !5 of relay D will close before polar contact 29 reverses, an auxiliary holding circuit for relay E will be effective over back contact [5 and wire 36, to bridge the reversal time of contact 29, which contact when closed will reestablish the holding circuit through the proper thermal relay contact.

When an overload occurs, the contact of the active thermal relay will open, breaking the holding circuit for relay E, and interrupting the motor circuit at front contact I1, whereupon the switch may be restored to its initial position by a reversal of relay D, which will pick up relay E and will select a motor circuit through the remaining thermal relay, without the necessity for waiting for the first thermal relay to cool. This feature of immediate reversibility is of considerable practical importance because it eliminates trafiic delays. Should the operator wish to restore the switch to its initial position from any part of its stroke, after having initiated a switch movement, he may do this at any time by reversing pole-changer P. It will be apparent, therefore, that the apparatus embodying my invention provides full control of the switch at all times.

One feature of my invention is that it provides overload protection and makes it possible for the switch to be restored to its initial position immediately, following an operation of the overload apparatus, by proper manipulation of the polechanger P by the operator of the interlocking machine.

Although I have herein shown and described only two forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the'scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a railway switch, an electric 'motor for operating said switch, a polarized relay,

an overload relay, a thermal relay having a heating element and a normally closed contact, a pick-up circuit for said overload relay including a back contact of said polarized relay and said thermal relay contact, a stick circuit for said overload relay including a front contact thereof and said thermal relay contact, circuits for said motor controlled by said polarized relay and including the heating element of said thermal relay as well as a front contact of said overload relay, a circuit for said polarized relay including a pole-changer and a front contact of said overload relay, and'a shunt around said overload relay contact in said polarized relay circuit which shunt includes a front neutral contact of the polarized relay.

2. In combination, a railway switch, an electric motor for operating said switch, a polarized relay, an overload relay, a thermal relay having a heating element and a normally closed contact, a pick-up circuit for said overload relay including a back contact of said polarized relay and said thermal relay contact, a stick circuit for said overload relay including a front contact thereof and said thermal relay contact, circuits for said motor controlled by said polarized relay and including the heating element of said thermal reteam for said polarized relay includ ng. apart. changer and a, front co ntact of saidstarlets re lay, and a shunt around 'said overload relay contact in said polarized relay circuit which shunt includes a front neutral'contactof the polarized relay. 7

4. In combination, a railway switch, an electric motor for operating said switch, a polarized relay, an overload relay, a thermal relay having a heating element and a normally closed contact, means for energizing said overload relay when saidpolar-' ized relay is deenergized and said thermal relay contact is closed, a stick circuit for saidoverload relay controlled by said thermal relay contact, circuits for said motor controlled by said polarized relay and by said overloadrelayv and including said thermal relay heating element, and means for reversibly energizing said polarized relay.

5. In combination, a railway switch, an electric motor for operating said switch, a control re-' lay, an overload relay, a thermal relay having a heating element and a normally closed contact,

means for energizing said overload relay when said control relay is deenergized and said thermal relay contact is closed, a stick circuit for said overload relay controlled by said thermal relay contact, a circuit forsaid motor controlled by said control relay and by said overload relay and including said thermal relay heating element, and controlling means for said control relay.

6. In combination, a railway switch, an electric motor for operating said switch, a control relay, an overload relay, a pick-up circuit forsaid overload relay including a back contact of said control relay, a stick circuit for said overload relay, means responsive to the magnitude of the curernt supplied to said motor for governing both said pick-up and said stick circuits when said current exceeds a predetermined value, means including a front contact of said control relay as well as a front supplying current to said motor, and means in-.

cluding a front contact of said overload relay for governing said control relay.

8. In combination, a railway'switch, an electric motor for operating said switch, a control relay, an overload relay, a pick-up circuit for said overload relay, a stick circuit for said overload relay, means responsive to the magnitude of the current'supy, and aid ,ove,

Contact of said overloadrelay for governing said con l ,r nand a branch a a fwii Sa ve lda Yr lam nta t, e ve nedb '.said. ntr lirslay: Ilncbmhina ia a mar a le d te a ec ric werl ad rsl ia ifikr p e r i dr S we a relayinclu'ding a back contact of said control relay, a stic'k'circ'uit for saidoverload ream-means effective when the movement of 'said device beconiesobs'tructed for governing both said pick-up and saidstick circuits, means manning a front contacto'f said control relay as'well as afront coiltrol relay. a l

10. In combination, a movable device,.an.electricmotor for operating said device, a control reoverload relay, a stick circuit for said overload relay, means effective when the movement of said device becomes obstructed for governing both said pick-up andsaid stick circuits, means governed by ri' d cbsr s'sa ev c a cs ir rlay I tact of said overload relay for sup lying currentv .to said motor, and means for governing said conlay,an overload relay, a pick-up circuit'for said said control relay and said overload relay for supplying current to said motor, and means including a front contact of said overload relay for governof said device becomes obstructed for governing 1 both said pick-up and said stick circuits, means governed by said control relay and said overload relay for supplying current to said motor, means including a front contact of said overload relay for governing said control relay, and a branch path around said overload relay contact governed by said control relay.

12. In combination, arailwayswitcnan electric motor for operating said switch, a polarized relay, an overload relay, a normal anda reverse thermal relay each having a heating element and a normally closedcontact, a pick-up circuit for said overload relay including a back contact of said polarized relay, a normal stick circuit for said overload relay including a front contact thereof and a normal'polar contact of said polarized relay as well as the contact of said normal thermal relay, a reverse stick circuitfor said overload relay including said front contact thereof and a reverse polar contact of said polarized relay as well as the contact of said reverse thermal relay, 2, normal and. a reverse circuit for said motor'controlled by said polarized relay and including the heating element of said normal and said reverse thermal relay respectively and a 7 second front contact of said overload relay, and means for reversibly energizing said polarized relay.

13. In combination, a railway switch, an elecv relay and the contact of said reverse thermal relay, a normal and a reverse circuit for said motor governed by said control relay and by said overload relay and including the heating element of said normal and said reverse thermal relay respectively, and controlling means for said 7 control I relay.

14. In combination, a railway switch, an elec tric motor for operating said switch, an overload relay, a normal and a reverse thermal relay each having a heating element and a contact, a normal and a reverse stick circuit for said overload relay controlled by the contact of saidlnormal and said reverse thermal relay respectively, a normal and a reverse operatingcircuit for said motor controlled by said overload relay and including the heating winding of said normal and said reverse thermal relay respectively, and

manually. operable means for controlling said normal and said reverse operating circuits and for energizing said overload relay. 15. In combination, a railway switch, an electric motor foroperating said switch, a control relay, an overload relay, a pick-up circuit for said overload relay including a back contact of said control relay, a stick circuit for said overload relay, means responsive to the magnitude of the current supplied to said motor for governing said stick circuit when said current exceeds a predetermined value, means including a front contact of said control relay as well as a front contact of said overload relay for supplying current to said motor; and means for governing said control relay.

' ROBERT M. GILSON. 

